Evaluation of the fatigue life of a sintered machine element under the sliding/rolling contact condition based on fracture mechanics

摘要

In order to evaluate the surface durability of sintered machine elements, the fatigue lives of 28 kinds of sintered roller under a sliding/rolling contact condition were estimated using Paris's law based on linear fracture mechanics. The fatigue tests were conducted using a two-cylinder testing machine. The stress intensity factor for the mode Ⅱ under the Hertzian contact condition was calculated using the finite element model. The value of the stress intensity factor became larger as the crack length became longer to the contact surface, and the value of the stress intensity factor range was independent of the crack angle. It could be clarified that the fatigue lives of the sintered rollers depended on the pore diameter and the hardness. It was obvious that the pore distribution has to be taken into consideration to estimate the fatigue lives of the sintered rollers more precisely.